Proliferation Of Bone Marrow Mesenchymal Stem Cells Research Articles

Effects of interleukin-10 treated macrophages on bone marrow mesenchymal stem cells via signal transducer and activator of transcription 3 pathway.

Alveolar bone defects caused by inflammation are an urgent issue in oral implant surgery that must be solved. Regulating the various phenotypes of macrophages to enhance the inflammatory environment can significantly affect the progression of diseases and tissue engineering repair process. To assess the influence of interleukin-10 (IL-10) on the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) following their interaction with macrophages in an inflammatory environment. IL-10 modulates the differentiation of peritoneal macrophages in Wistar rats in an inflammatory environment. In this study, we investigated its impact on the proliferation, migration, and osteogenesis of BMSCs. The expression levels of signal transducer and activator of transcription 3 (STAT3) and its activated form, phosphorylated-STAT3, were examined in IL-10-stimulated macrophages. Subsequently, a specific STAT3 signaling inhibitor was used to impede STAT3 signal activation to further investigate the role of STAT3 signaling. IL-10-stimulated macrophages underwent polarization to the M2 type through substitution, and these M2 macrophages actively facilitated the osteogenic differentiation of BMSCs. Mechanistically, STAT3 signaling plays a crucial role in the process by which IL-10 influences macrophages. Specifically, IL-10 stimulated the activation of the STAT3 signaling pathway and reduced the macrophage inflammatory response, as evidenced by its diminished impact on the osteogenic differentiation of BMSCs. Stimulating macrophages with IL-10 proved effective in improving the inflammatory environment and promoting the osteogenic differentiation of BMSCs. The IL-10/STAT3 signaling pathway has emerged as a key regulator in the macrophage-mediated control of BMSCs' osteogenic differentiation.

Preliminary study on the mechanism by which exosomes derived from human exfoliated deciduous teeth improve the proliferation and osteogenic inhibitory effect of glucocorticoid-induced BMSCs

BackgroundSteroid-induced osteonecrosis of the femoral head (SONFH) is a disease characterized by a collapsed femoral head caused by the overuse of glucocorticoids. Dysfunction of bone marrow mesenchymal stem cells (BMSCs) is an important pathological feature of SONFH. In this study, we investigated whether exosomes from SHEDs (stem cells from human exfoliated deciduous teeth) have a therapeutic effect on glucocorticoid-induced inhibition of proliferation and osteogenesis in BMSCs, and elucidated the underlying mechanisms involved. MethodsPrimary dental pulp cells were isolated and cultured from human deciduous tooth pulp, SHEDs were isolated and purified by the limiting dilution method and exosomes were isolated from the supernatants of SHEDs by ultracentrifugation. The cell surface markers CD31, CD34, CD45, CD73, CD90 and CD105 were detected by flow cytometry. A Cell-Counting-Kit-8 assay was used to detect cell activity. ALP and Alizarin Red staining were used to identify osteogenic differentiation ability, and exosomes were identified using transmission electron microscopy, NanoFCM and Western blotting. PKH67 fluorescence was used to track the uptake of exosomes by BMSCs. Transcriptome analysis combined with quantitative real-time PCR was used to explore the underlying mechanism involved. ResultsExosomes secreted by SHEDs can be endocytosed by BMSCs, and can partially reverse the inhibitory effects of glucocorticoids on the viability and osteogenic differentiation of BMSCs. Transcriptome sequencing analysis revealed that the differentially expressed mRNAs regulated by SHED-derived exosomes were enriched mainly in signaling pathways such as the apoptosis pathway, the PI3K-Akt signaling pathway, the Hippo signaling pathway and the p53 signaling pathway. qPCR showed that SHED-derived exosomes reversed the dexamethasone-induced upregulation of HGF and ITGB8 expression and the inhibition of EFNA1 expression, but further increased the dexamethasone-induced downregulation of IL7 expression. In conclusion, SHED-derived exosomes partially reversed the inhibitory effects of glucocorticoids on BMSC proliferation and osteogenesis by inhibiting the expression of HGF, ITGB8 and IL7, and upregulating the expression of EFNA1.

YTHDF2-Mediated m6A methylation inhibition by miR27a as a protective mechanism against hormonal osteonecrosis in BMSCs

BackgroundWith the increasing incidence of steroid-induced necrosis of the femoral head (SNFH), numerous scholars have investigated its pathogenesis. Current evidence suggests that the imbalance between lipogenesis and osteoblast differentiation in bone marrow mesenchymal stem cells (BMSCs) is a key pathological feature of SNFH. MicroRNAs (miRNAs) have strong gene regulatory effects and can influence the direction of cell differentiation. N6-methyladenosine (m6A) is a prevalent epigenetic modification involved in diverse pathophysiological processes. However, knowledge of how miRNAs regulate m6A-related factors that affect BMSC differentiation is limited.ObjectiveWe aimed to investigate the role of miR27a in regulating the expression of YTHDF2 in BMSCs.MethodsWe compared miR27a, YTHDF2, and total m6A mRNA levels in SNFH-affected and control BMSCs. CCK-8 and TUNEL assays were used to assess BMSC proliferation and apoptosis. Western blotting and qRT‒PCR were used to measure the expression of osteogenic (ALP, RUNX2, and OCN) and lipogenic (PPARγ and C/EBPα) markers. Alizarin Red and Oil Red O staining were used to quantify osteogenic and lipogenic differentiation, respectively. miR27a was knocked down or overexpressed to evaluate its impact on BMSC differentiation and its relationship with YTHDF2. Bioinformatics analyses identified YTHDF2 as a differentially expressed gene in SNFH (ROC analysis) and revealed potential signaling pathways through GSEA. The effects of YTHDF2 silencing on the lipogenic and osteogenic functions of BMSCs were assessed.ResultsmiR27a downregulation and YTHDF2 upregulation were observed in the SNFH BMSCs. miR27a knockdown/overexpression modulated YTHDF2 expression, impacting BMSC differentiation. miR27a silencing decreased m6A methylation and promoted osteogenic differentiation, while YTHDF2 silencing exerted similar effects. GSEA suggested potential signaling pathways associated with YTHDF2 in SNFH.ConclusionmiR27a regulates BMSC differentiation through YTHDF2, affecting m6A methylation and promoting osteogenesis. This finding suggests a potential therapeutic target for SNFH.

Extracellular Vesicles Derived from Neutrophils Accelerate Bone Regeneration by Promoting Osteogenic Differentiation of BMSCs.

The reconstruction of bone defects has been associated with severe challenges worldwide. Nowadays, bone marrow mesenchymal stem cell (BMSC)-based cell sheets have rendered this approach a promising way to facilitate osteogenic regeneration in vivo. Extracellular vesicles (EVs) play an essential role in intercellular communication and execution of various biological functions and are often employed as an ideal natural endogenous nanomedicine for restoring the structure and functions of damaged tissues. The perception of polymorphonuclear leukocytes (neutrophils, PMNs) as indiscriminate killer cells is gradually changing, with new evidence suggesting a role for these cells in tissue repair and regeneration, particularly in the context of bone healing. However, the role of EVs derived from PMNs (PMN-EVs) in bone regeneration remains largely unknown, with limited research being conducted on this aspect. In the current study, we investigated the effects of PMN-EVs on BMSCs and the underlying molecular mechanisms as well as the potential application of PMN-EVs in bone regeneration. Toward this end, BMSC-based cell sheets with integrated PMN-EVs (BS@PMN-EVs) were developed for bone defect regeneration. PMN-EVs were found to significantly enhance the proliferation and osteogenic differentiation of BMSCs in vitro. Furthermore, BS@PMN-EVs were found to significantly accelerate bone regeneration in vivo by enhancing the maturation of the newly formed bone in rat calvarial defects; this is likely attributable to the effect of PMN-EVs in promoting the expression of key osteogenic proteins such as SOD2 and GJA1 in BMSCs. In conclusion, our findings demonstrate the crucial role of PMN-EVs in promoting the osteogenic differentiation of BMSCs during bone regeneration. Furthermore, this study proposes a novel strategy for enhancing bone repair and regeneration via the integration of PMN-EVs with BMSC-based cell sheets.

Beta-adrenergic receptor antagonist propranolol prevents bisphosphonate-related osteonecrosis of the jaw by promoting osteogenesis

Background/purposeBisphosphonate-related osteonecrosis of the jaw (BRONJ), a complication arising from the use of bisphosphonates (BPs), inflicts long-term suffering on patients. Currently, there is still a lack of effective treatments. This study aimed to explore the preventive effects of propranolol (PRO) on BRONJ in vitro and in vivo, given PRO's potential in bone health enhancement. Materials and methodsIn vitro, effect of PRO on zoledronic acid (ZA)-pretreated bone marrow mesenchymal stem cells (BMSCs) was detected by cell counting kit-8, alkaline phosphatase (ALP) staining, alizarin red staining, real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot. In vivo, forty mice were divided into four groups: control, ZA, PRO, and ZA-PRO. The maxillary extraction sockets sides were analyzed with micro-CT and histomorphometry. Hematoxylin-eosin (H&E), Masson staining, immunofluorescence staining of ALP, bone morphogenetic protein 2 (BMP2), runt-related transcription factor 2 (RUNX2) and TUNEL staining were performed. ResultsPRO increased proliferation and osteogenic differentiation of BMSCs. PRO stimulated bone formation and facilitated the healing process in zoledronic acid-induced osteonecrosis of jaw in mouse model. Compared with ZA group, control and PRO group showed more BMP2+, RUNX2+, and ALP+ cells (P < 0.05). However, PRO rescued the decreased expression of ALP, RUNX2, BMP2 due to ZA and decreased the expression of TUNEL (P < 0.05). ConclusionThe findings suggest that propranolol may offer a promising preventive strategy against BRONJ by enhancing bone regeneration. This research contributes to the understanding of the pathogenesis of BRONJ and opens avenues for potential treatments of BRONJ focusing on β-adrenergic signaling.

Boswellic acid as a potential adjunct for bone healing after endodontic surgery: In vitro study

Abstract Introduction: The role of Acetyl -11-keto-β-boswellic acid (AKBA) in regulating osteoblast differentiation was recently brought to light. Therefore, the current study was designed to explore the osteogenic differentiation capability of AKBA on bone marrow mesenchymal stem cells (BMMSCs) as a potential therapeutic agent to accelerate the healing process in apicoectomy. Materials and Methods: BMMSCs were characterized by flow cytometry. Cellular viability and proliferation assays were used with different concentrations of AKBA. Cells were divided into 5 groups to test osteogenic differentiation: Group I: negative control, Group II: positive control, Group III: BMMSCs were treated with 1 μM AKBA, Group IV: BMMSCs were treated with 0.1 μM AKBA, and Group V: BMMSCs were treated with 0.01 μM AKBA. Mineralization assays and gene expression analysis were assessed, and the significance difference between groups was established at P &lt; 0.05. Results: The flow cytometry analysis demonstrated that BMMSCs had positive expression for mesenchymal stem cell marker and negative expression for hematopoietic markers. The concentration of 0.01 μM gave significantly higher cell density than the untreated cells after 7 days (P &lt; 0.05). Cells treated with 0.1 and 0.01 μM AKBA revealed a significantly higher ALP activity, alizarin red, and von Kossa staining than control groups (P &lt; 0.05). High expression of osteogenic genes was detected in BMMSCs treated with 0.1 μM AKBA (P &lt; 0.05). Conclusions: It was declared that the concentration of 0.1 μM AKBA has no toxicity on BMMSC viability and proliferation with an impact on BMMSC osteogenic differentiation. Therefore, AKBA (0.01 μM) could be used in bone regeneration during periradicular surgery.

Bushen Huoxue recipe ameliorates ovarian function via promoting BMSCs proliferation and homing to ovaries in POI mice

BackgroundPremature ovarian insufficiency (POI) is a tricky puzzle in the field of female reproductive medicine. Bushen Huoxue recipe (BHR), a traditional Chinese medicine compound based on the combination of kidney-tonifying and blood-activating functions, has shown excellent efficacy in improving female irregular menstruation, POI, and infertility. However, the potential mechanism of BHR in POI treatment has not yet been elucidated. Bone marrow mesenchymal stem cells (BMSCs), a type of pluripotent stem cells, have received increasing attention for their significant role in improving ovarian function and restoring fertility in women with POI. PurposeThis study aimed to evaluate the therapeutic effect of BHR in POI mice and explore its potential mechanism. MethodsA POI mouse model was established with a single intraperitoneal injection of 120 mg/kg cyclophosphamide (CTX). Distilled water, BHR, or dehydroepiandrosterone was administered via gavage for 28 consecutive days. The effect of BHR on ovarian function in POI mice was evaluated by assessing the estrous cycle, ovarian morphology, follicular development, hormone levels, and angiogenesis. The proportion of BMSCs in bone marrow, peripheral blood, and ovary was analyzed via flow cytometry, and the level of molecules mediating migration and homing in ovary was measured. Cell viability assays, scratch healing assays and transwell migration assays were performed to explore the effect of BHR on BMSCs proliferation and migration in vitro, and its potential mechanism was explored. ResultsBHR significantly ameliorated estrous cycle disorders, hormone disorders, ovarian morphology, ovarian microvascular formation, and ovarian reserve in POI mice. Meanwhile, the number of BMSCs number in the bone marrow, peripheral blood, and ovary was apparently increased. Of note, BHR increased the level of hepatocyte growth factor (HGF)/cellular mesenchymal epithelial transition factor (cMET) and stromal cell-derived factor-1(SDF-1)/CXC chemokine receptor 4 (CXCR4) in the ovaries of POI mice. Moreover, BHR treatment promoted BMSCs proliferation and migration in vitro, with a significant increase in the level of proliferating cell nuclear antigen, cMET, and CXCR4. ConclusionsBHR effectively restored ovarian reserve, ovarian function, and ovarian angiogenesis in CTX-induced POI mice. In addition, BHR promoted BMSCs proliferation, migration, and homing to the ovary, which was mediated by the SDF-1/CXCR4 and HGF/cMET signaling axis. Finally, the amelioration of ovarian reserve and ovarian function in CTX-induced POI mice by BHR may be related to its promotion of endogenous BMSCs proliferation and homing.

High-strength double-network silk fibroin based hydrogel loaded with Icariin and BMSCs to inhibit osteoclasts and promote osteogenic differentiation to enhance bone repair

Large bone defects cause significant clinical challenges due to the lack of optimal grafts for effective regeneration. The tissue engineering way that requires the combination of biomaterials scaffold, stem cells and proper bioactive factors is a prospective method for large bone repair. Here, we synthesized a three-arm host-guest supramolecule (HGSM) to covalently crosslinking with the naturally derived polymer methacrylated silk fibroin (SFMA). The combination of HGSM and SFMA can form a high strength double-crosslinked hydrogel HGSFMA, that serve as the hydrogel scaffold for bone marrow mesenchymal stem cells (BMSCs) growing. Icariin (ICA) loaded in the HGSFMA hydrogel can promote the osteogenesis efficiency of BMSCs and inhibit the osteoclasts differentiation. Our findings demonstrated that the HGSFMA/ICA hydrogel effectively promoted the in vitro adhesion, proliferation, and osteogenic differentiation of BMSCs. Rat femoral defects model show that this hydrogel can completely repair femoral damage within 4 weeks and significantly promote the secretion of osteogenesis-related proteins. In summary, we have prepared an effective biomimetic bone carrier, offering a novel strategy for bone regeneration and the treatment of large-scale bone defects.

Enhancing osteoblast proliferation and bone regeneration by poly (amino acid)/selenium-doped hydroxyapatite

Among various biomaterials employed for bone repair, composites with good biocompatibility and osteogenic ability had received increasing attention from biomedical applications. In this study, we doped selenium (Se) into hydroxyapatite (Se-HA) by the precipitation method, and prepared different amounts of Se-HA-loaded poly (amino acid)/Se-HA (PAA/Se-HA) composites (0, 10 wt%, 20 wt%, 30 wt%) by in-situ melting polycondensation. The physical and chemical properties of PAA/Se-HA composites were characterized by x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and their mechanical properties. XRD and FT-IR results showed that PAA/Se-HA composites contained characteristic peaks of PAA and Se-HA with amide linkage and HA structures. DSC and TGA results specified the PAA/Se-HA30 composite crystallization, melting, and maximum weight loss temperatures at 203.33 °C, 162.54 °C, and 468.92 °C, respectively, which implied good thermal stability. SEM results showed that Se-HA was uniformly dispersed in PAA. The mechanical properties of PAA/Se-HA30 composites included bending, compressive, and yield strengths at 83.07 ± 0.57, 106.56 ± 0.46, and 99.17 ± 1.11 MPa, respectively. The cellular responses of PAA/Se-HA composites in vitro were studied using bone marrow mesenchymal stem cells (BMSCs) by cell counting kit-8 assay, and results showed that PAA/Se-HA30 composites significantly promoted the proliferation of BMSCs at the concentration of 2 mg ml−1. The alkaline phosphatase activity (ALP) and alizarin red staining results showed that the introduction of Se-HA into PAA enhanced ALP activity and formation of calcium nodule. Western blotting and Real-time polymerase chain reaction results showed that the introduction of Se-HA into PAA could promoted the expression of osteogenic-related proteins and mRNA (integrin-binding sialoprotein, osteopontin, runt-related transcription factor 2 and Osterix) in BMSCs. A muscle defect at the back and a bone defect at the femoral condyle of New Zealand white rabbits were introduced for evaluating the enhancement of bone regeneration of PAA and PAA/Se-HA30 composites. The implantation of muscle tissue revealed good biocompatibility of PAA and PAA/Se-HA30 composites. The implantation of bone defect showed that PAA/Se-HA30 composites enhanced bone formation at the defect site (8 weeks), exhibiting good bone conductivity. Therefore, the PAA-based composite was a promising candidate material for bone tissue regeneration.

Fabrication and application of salicin-polycaprolactone 3D-printed scaffold in the healing of femur bone defects

Polycaprolactone (PCL) is a suitable material for bone repair due to good biocompatibility and mechanical properties. However, low bioactivity and hydrophobicity pose major challenges for its biomedical applications. To overcome these limitations, PCL-based scaffolds loaded with bioactive agents have been developed. Salicin (Sal) is an anti-inflammatory and analgesic herbal glycoside with osteogenic potential. In the present study, we aimed to produce a Sal-laden PCL (PCL–Sal) scaffold for bone healing applications. Three-dimensional scaffolds were produced and their biocompatibility, and physical-chemical characteristics were determined. The osteogenic potential of the PCL (PCL) and PCL–Sal scaffolds was evaluated using bone marrow mesenchymal stem cells (BMSCs). Scaffolds were implanted into a 5 mm bone defect created in the femur of adult rats, and the new bone fraction was determined using micro-computed tomography scanning at one-month follow-up. PCL–Sal scaffold had a structure, porosity, and fiber diameter suitable for bone construction. It also possessed a higher rate of hydrophilicity and bioactivity compared to the PCL, providing a suitable surface for the proliferation and bone differentiation of BMSCs. Furthermore, PCL–Sal scaffolds showed a higher capacity to scavenge free radicals compared to PCL. The improved bone healing potential of the PCL–Sal scaffold was also confirmed according to in vivo implantation results. Our findings revealed that the Sal-laden implant could be considered for bone repair due to desirable characteristics of Sal such as hydrophilicity, surface modification for cell attachment, and antioxidant properties.

Functionalized chitosan hydrogel promotes osseointegration at the interface of3D printed titanium alloy scaffolds

Autogenous bone transplantation is a prevalent clinical method for addressing bone defects. However, the limited availability of donor bone and the morbidity associated with bone harvesting have propelled the search for suitable bone substitutes. Bio-inspired scaffolds, particularly those fabricated using electron beam melting (EBM) deposition technology, have emerged as a significant advancement in this field. These 3D-printed titanium alloy scaffolds are celebrated for their outstanding biocompatibility and favorable elastic modulus. Thermosensitive chitosan hydrogel, which transitions from liquid to solid at body temperature, serves as a popular carrier in bone tissue engineering. Icariin (ICA), known for its efficacy in promoting osteoblast differentiation from bone marrow mesenchymal stem cells (BMSCs), plays a crucial role in this context. We developed a system combining a 3D-printed titanium alloy with a thermosensitive chitosan hydrogel, capable of local bone regeneration and integration through ICA delivery. Our in vitro findings reveal that this system can gradually release ICA, demonstrating excellent biocompatibility while fostering BMSC proliferation and osteogenic differentiation. Immunohistochemistry and Micro-CT analyses further confirm the effectiveness of the system in accelerating in vivo bone regeneration and enhancing osseointegration. This composite system lays a significant theoretical foundation for advancing local bone regeneration and integration.

Exosomes from young plasma alleviate osteoporosis through miR-217-5p-regulated osteogenesis of bone marrow mesenchymal stem cell

Osteoporosis, increasingly prevalent among the aging population, poses a global health challenge. Current treatments, often limited by prolonged treatment durations, serious side effects, and suboptimal efficacy, necessitate innovative approaches. Building on previous research that highlighted the rejuvenating potential of young blood in organ vitality. This study focused on the role of exosomes and exosomal miRNA. Specifically, we investigated the efficacy of exosomes derived from young plasma (Y-Exos) in mitigating osteoporosis, contrasting them with exosomes from aged plasma (A-Exos). Our in vitro analysis involved co-culturing bone marrow mesenchymal stem cells (BMSCs) with Y-Exos or A-Exos, assessing their impact on BMSCs migration, proliferation, and osteogenic differentiation. Y-Exos exhibited a marked enhancement in BMSCs proliferation, migration, and osteogenic differentiation compared to A-Exos. Corresponding in vivo studies corroborated these findings, demonstrating that Y-Exos significantly alleviated osteoporosis, whereas A-Exos impeded bone regeneration. Furthermore, our research identified exosomal miR-217–5p as a pivotal contributor to the osteoprotective effects of Y-Exos. Our work provided a potential strategy for advancing the clinical treatment of osteoporosis.

Dimethyloxallyl glycine-loaded mesoporous bioactive glass/poly(D,L-lactide) composite scaffolds with ultrasound stimulation for promoting bone repair.

Introduction: Bone tissue engineering is considered the ideal approach for bone repair. Mesoporous bioactive glass (MBG) possesses the characteristics of high drug-loading capacity and bioactivity. Low-intensity pulsed ultrasound contributes to promoting fracture healing and bone defect repair, and dimethyloxalyl glycine (DMOG) is a small molecular inhibitor that can suppress prolyl hydroxylase, reducing the degradation of hypoxia-inducible factor. Methods: In this study, we proposed to prepare DMOG-loaded MBG/poly(D,L-lactide) composite scaffolds (DMOG-MBG/PDLLA) for promoting bone repair. The effects of ultrasound stimulation and DMOG release on the cell responses of rat bone marrow mesenchymal stem cells (BMSCs) and human umbilical vein endothelial cells (HUVECs) and bone repair in vivo were investigated. Results and Discussion: The results showed that both ultrasound stimulation and DMOG release could promote the proliferation, adhesion and differentiation of BMSCs and HUVECs, respectively. After the implantation of scaffolds in rat cranial bone defect model for 8 weeks, the results indicated that the combined ultrasound stimulation and DMOG release contributed to the highest ability for promoting bone repair. Hence, the DMOG-MBG/PDLLA scaffolds with ultrasound stimulation are promising for application in bone repair.

Osteogenesis or Apoptosis-Twofold Effects of Zn2+ on Bone Marrow Mesenchymal Stem Cells: An In Vitro and In Vivo Study.

Zinc (Zn) is a bioabsorbable metal that shows great potential as an implant material for orthopedic applications. Suitable concentrations of zinc ions promote osteogenesis, while excess zinc ions cause apoptosis. As a result, the conflicting impacts of Zn2+ concentration on osteogenesis could prove to be significant problems for the creation of novel materials. This study thoroughly examined the cell viability, proliferation, and osteogenic differentiation of rat bone marrow mesenchymal stem cells (rBMSCs) cultured in various concentrations of Zn2+ in vitro and validated the osteogenesis effects of zinc implantation in vivo. The effective promotion of cell survival, proliferation, migration, and osteogenic differentiation of bone marrow mesenchymal stem cell (BMSCs) may be achieved at a low concentration of Zn2+ (125 μM). The excessively high concentration of zinc ions (>250 μM) not only reduces BMSCs' viability and proliferation but also causes them to suffer apoptosis due to the disturbed zinc homeostasis and excessive Zn2+. Moreover, transcriptome sequencing was used to examine the underlying mechanisms of zinc-induced osteogenic differentiation with particular attention paid to the PI3K-AKT and TGF-β pathways. The present investigation elucidated the dual impacts of Zn2+ microenvironments on the osteogenic characteristics of rBMSCs and the associated processes and might offer significant insights for refining the blueprint for zinc-based biomaterials.

The biofilm removal effect and osteogenic potential on the titanium surface by electrolytic cleaning: An invitro comparison of electrolytic parameters and five techniques.

To determine the optimal current and time of electrolytic cleaning (EC), compare its biofilm removal effect with generic treatments and evaluate the influence of EC to surface characteristics and osteogenic potential of SLA titanium (Ti) discs. The six-species biofilm-covered Ti discs were placed as cathodes in physiologic saline and subjected to various current and time treatments. The residual biofilms were evaluated to determine the optimal parameters. The contaminated Ti discs were randomized and treated by rotating Ti brush; ultrasonic-scaling with metal tips; ultrasonic-scaling with PEEK tips; air-polishing and EC. The residual biofilms were compared using a lipopolysaccharide kit (LPS), scanning electron microscope (SEM), confocal laser scanning microscopy and colony-forming unit counting. Non-contaminated Ti discs were treated and characterized. The bone marrow mesenchymal stem cells (BMSCs) were cultured on treated non-contaminated Ti discs. The adhesion, proliferation, alkaline phosphatase (ALP) activity and osteocalcin level of BMSCs were assessed. The parameters at 0.6A5min were considered optimal. For LPS and SEM, EC promoted a significantly greater biofilm removal than the other groups. There were no changes in the Ti discs' colour, topography, roughness and chemical elements after EC, and the electrolysis-treated Ti discs obtained a super-hydrophilic surface. EC positively impacted the proliferation and ALP activity of BMSCs, surpassing the efficacy of alternative treatments. EC achieves a near-complete eradication of contaminants on the SLA surface, causes no surface damage with improved hydrophilicity, and promotes the early osteogenic response of BMSCs, which makes it a promising treatment for peri-implantitis.

Fabrication and evaluation of composite hydroxyapatite coating on ordered micro-/nanotextured titanium surface

Objective: To develope a titanium specimen with good osteogenic activity through fabrication of a composite hydroxyapatite coating on ordered micro-/nanotextured titanium surface. Methods: An ordered micro-/nanotextured structure was prepared on the surface of titanium (the control), and then hydroxyapatite was deposited on the as-prepared ordered micro-/nanotextured structure by alternative loop immersion method. The ordered micro-/nanotextured structures before and after hydroxyapatite deposition were denoted as HA and MN, respectively. Surface morphology was observed using a scanning electron microscope. Bone marrow mesenchymal stem cells (BMMSC) were seeded on the surface of three different materials. Cell morphology was observed with a scanning electron microscope. Cell adhesion and cell proliferation were evaluated using 4', 6-diamidino-2-phenylindole staining and cell counting kit-8 assay, respectively. Extracellular matrix mineralization and the expression levels of osteogenesis-related genes were evaluated by alizarin red staining and real-time quantitative PCR, respectively. Each group has three samples in every experiment. Results: After alternative loop immersing, the MN's original microholes (20 μm in diameter) were retained, and the uniform petal-like hydroxyapatite was deposited on the MN's original titania nanotubes (70 nm in diameter). Compared with the control, BMMSC on MN and HA elongated further and intersected along the micron structure with noticeable pseudopodia and pseudoplates, and the trend was more pronounced especially on HA. The number of early adherent cells on HA was remarkably larger than that on the control and MN at each time point (P<0.05). On day 1, the A value of cell proliferation on HA was significantly higher than that on the control and MN (P<0.05). The A value of cell proliferation on HA was significantly lower than that on the control and MN on day 3 (P<0.05). On day 7, the A value of cell proliferation on HA was significantly lower than that on MN (P<0.05), but there was no statistically significant difference in the A value of cell proliferation between HA and the control on day 7 (P>0.05). The Avalue of extracellular matrix mineralization on HA (0.607±0.011) was significantly higher than that on the control and MN (0.268±0.025 and 0.522±0.022, respectively) (t=-0.25, P<0.001; t=-0.34, P<0.001). The expression levels of bone related genes on HA were significantly higher than those on the control and MN (P<0.05). Conclusions: HA could promote the BMMSC adhesion and osteogenic differentiation, support BMMSC proliferation, and demonstrate good osteogenic activity.

The Protective Effect of Crocin on Rat Bone Marrow Mesenchymal Stem Cells Exposed to Aluminum Chloride as an Endocrine Disruptor.

Mesenchymal Stem Cells (MSCs) have the ability to self-renew and proliferate which gives them healing properties in various tissues. Aluminium chloride (AlCl3) is a chemical compound with harmful effects on health; oxidative stress caused by Aluminium has been reported previously. Crocin, a major component of Crocus sativus (saffron), has antioxidant properties and has shown therapeutic potential. Researchers have been looking for ways to reduce the harmful effects of AlCl3. To investigate whether crocin can reduce AlCl3 cytotoxicity, rat Bone Marrow Mesenchymal Stem Cells (BM-MSCs) were isolated, cultured and divided into four experimental groups. The first group was the control, which was untreated cells. The second and third groups were treated with crocin (50, 100, 250, 500 μM) and AlCl3 (20, 25, 30 mM) for 24 hr. The fourth group was pre-treated with crocin (250, 500 μM) for 24 hr and then treated with AlCl3 (20 mM) overnight. Cytotoxicity was assessed using the MTT assay. Mineralization was evaluated by alizarin red staining. Sox-2 and E-cadherin expression were measured using real-time PCR. The results showed that AlCl3 caused cytotoxicity on BM-MSCs and decreased the mRNA expression of Sox-2 and E-cadherin, which are important for the maintenance of self-renewal and proliferation of BM-MSCs. In contrast, crocin protected the self-renewal characteristic of BM-MSCs by increasing Sox-2 expression and also preserved the proliferative effects on BM-MSCs by upregulating E-cadherin expression (***p≤0.001). Overall, the study suggests that crocin can protect BM-MSCs from AlCl3-induced cytotoxicity by upregulate Sox-2 expression and E-cadherin expression. This suggests that crocin may be a potential therapeutic agent for the treatment of AlCl3-induced toxicity.

Experimental Studies on the Effects of Glycitinregulated TGF-β Signaling Pathway on the Proliferation, Osteogenic, and Lipogenic Differentiation of BMSCs

Background Glycitin, generated from the seeds of the legume soybean, has an essential function in antioxidant, obesity inhibition, and wound healing promotion. Furthermore, recent research has shown that it has anti-inflammatory and cartilage-protective properties. Objectives This study was designed to investigate the osteogenic effects of glycitin and the transforming growth factor-β (TGF-β) signaling pathway on bone marrow mesenchymal stem cells (BMSCs), as well as their interaction. Materials and Methods We isolated rabbit BMSCs by whole bone marrow adherent method and cultured, identified, and induced differentiation. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method was used to determine the proliferation ability of BMSCs with different concentrations of glycitin at different times; reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the expression levels of osteogenesis-related genes runt-related transcription factor 2 (Runx2), collagen type I (Col-1), and osteocalcin (OC) mRNA; and a kit was used to determine the activities of alkaline phosphatase and triglycerides (TG) in BMSCs. A Western blot was used to detect the expression of TGF-β protein in each group. Results On the fifth day of BMSC primary culture, the morphology of long spindle-shaped cells might be plentiful, dominated by a daisy-like or whirling arrangement. They proliferated rapidly and fused to 70%–80% on the eighth day of culture; the third generation of BMSCs was taken for phenotyping, and the detection results of flow cytometry analysis showed that the surface antigenic markers of BMSCs, CD44, and CD90 were positive, whereas CD34 and CD45 were negative; after osteogenic induction of BMSCs, visible calcified nodules were evident. There was cartilage matrix formation after osteogenic induction; glycitin promoted BMSC proliferation in a time-dependent and dose-dependent manner, and BMSC proliferation increased significantly at 20 µM glycitin for 3–5 days; glycitin increased the expression of Runx2, Col-1, and OC mRNA in BMSCs and increased the activity of alkaline phosphatase (ALP) while decreasing the activity of TG. Meanwhile, 20 µM glycitin dramatically increased the expression of TGF-β. Conclusion These findings imply that glycitin increases BMSCs proliferation and osteogenic differentiation. By regulating the TGF-β signaling pathway, glycitin modulates the differentiation of BMSCs into osteoblasts.

NCAM mimetic peptide P2 synergizes with bone marrow mesenchymal stem cells in promoting functional recovery after stroke

The neural cell adhesion molecule (NCAM) promotes neural development and regeneration. Whether NCAM mimetic peptides could synergize with bone marrow mesenchymal stem cells (BMSCs) in stroke treatment deserves investigation. We found that the NCAM mimetic peptide P2 promoted BMSC proliferation, migration, and neurotrophic factor expression, protected neurons from oxygen-glucose deprivation through ERK and PI3K/AKT activation and anti-apoptotic mechanisms in vitro. Following middle cerebral artery occlusion (MCAO) in rats, P2 alone or in combination with BMSCs inhibited neuronal apoptosis and induced the phosphorylation of ERK and AKT. P2 combined with BMSCs enhanced neurotrophic factor expression and BMSC proliferation in the ischemic boundary zone. Moreover, combined P2 and BMSC therapy induced translocation of nuclear factor erythroid 2-related factor, upregulated heme oxygenase-1 expression, reduced infarct volume, and increased functional recovery as compared to monotreatments. Treatment with LY294002 (PI3K inhibitor) and PD98059 (ERK inhibitor) decreased the neuroprotective effects of combined P2 and BMSC therapy in MCAO rats. Collectively, P2 is neuroprotective while P2 and BMSCs work synergistically to improve functional outcomes after ischemic stroke, which may be attributed to mechanisms involving enhanced BMSC proliferation and neurotrophic factor release, anti-apoptosis, and PI3K/AKT and ERK pathways activation.

CFL1 restores the migratory capacity of bone marrow mesenchymal stem cells in primary Sjögren's syndrome by regulating CCR1 expression

BackgroundPrimary Sjögren's syndrome (pSS) is a chronic systemic autoimmune disease. There is no relevant research on whether the migratory ability of bone marrow mesenchymal stem cells (BM-MSC) is impaired in patients with pSS (pSS-BMMSC). MethodsTrajectories and velocities of BM-MSC were analyzed. Transwell migration assay and wound healing assay were used to investigate the migratory capacity of BM-MSC. The proliferative capacity of BM-MSC was evaluated by EDU and CCK8 assay. RNA-seq analysis was then performed to identify the underlying mechanism of lentivirus-mediated cofilin-1 overexpression BM-MSC (BMMSCCFL1). The therapeutic efficacy of BMMSCCFL1 was evaluated in NOD mice. ResultsThe migratory capacity of pSS-BMMSC was significantly reduced compared to normal volunteers (HC-BMMSC). The expression of the motility-related gene CFL1 was decreased in pSS-BMMSC. Lentivirus-mediated CFL1 overexpression of pSS-BMMSC promoted the migration capacity of pSS-BMMSC. Furthermore, RNA-seq revealed that CCR1 was the downstream target gene of CFL1. To further elucidate the mechanism of CFL1 in regulating BM-MSC migration and proliferation via the CCL5/CCR1 axis, we performed a rescue experiment using BX431 (a CCR1-specific inhibitor) to inhibit CCR1. The results showed that CCR1 inhibitors suppressed the migration and proliferation capacity of MSC induced by CFL1. ConclusionThe pSS-BMMSC leads to impaired migration and proliferation, and overexpression of CFL1 can rescue the functional deficiency and alleviate disease symptoms in NOD mice. Mechanically, CFL1 can regulate the expression level of the downstream CCL5/CCR1 axis to enhance the migration and proliferation of BM-MSC.